Method to stop bleeding, with short hemostasis duration using a low dose of anticoagulant

ABSTRACT

Disclosed are methods and devices for obtaining patent hemostasis of the radial artery by compressing the uninstrumented ulnar artery to increase radial artery flow. The device comprises a band having an inflatable bladder for applying blunt pressure to the ulnar artery. The method comprises applying a pressure to the homolateral ulnar artery and applying a pressure to the radial artery at the access site to obtain hemostasis at the access site.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 16/138,958 filed Sep. 21, 2018, which is a non-provisional ofU.S. Provisional Application No. 62/653,172 filed Apr. 5, 2018 andcontinuation-in-part of co-pending U.S. patent application Ser. No.15/708,123, filed Sep. 18, 2017, which is non-provisional of U.S.Provisional Application No. 62/549,923 filed Aug. 24, 2017 and is acontinuation-in-part of U.S. patent application Ser. No. 15/426,056,filed Feb. 7, 2017, now U.S. Pat. No. 9,949,738, issued Apr. 24, 2018,which is non-provisional of U.S. Provisional Application No. 62/405,951filed Oct. 9, 2016 and is a continuation-in-part of U.S. patentapplication Ser. No. 15/340,023, filed Nov. 1, 2016, now U.S. Pat. No.9,592,060 issued Mar. 14, 2017, which is a continuation of U.S. patentapplication Ser. No. 15/062,150, filed Mar. 6, 2016, now U.S. Pat. No.9,510,838 issued Dec. 6, 2016, which is a continuation of U.S. patentapplication Ser. No. 13/941,219, filed Jul. 12, 2013, now U.S. Pat. No.9,308,000 issued Apr. 12, 2016.

The entire content of all above applications is incorporated herein byreference.

BACKGROUND OF INVENTION

a. Field of Invention

The invention relates generally to transradial catheterization methodsand devices used in said methods. In particular the invention concerns amethod of obtaining patent hemostasis of the radial artery bycompressing the un-instrumented ulnar artery to increase radial arteryflow while applying pressure to the radial artery access site. Theinvention further concerns a device for applying blunt pressure to theulnar artery, and a method of use.

b. Description of Related Art

Radial artery instrumentation is becoming increasingly prevalent withcardiovascular procedures performed via transradial access, providingimprovement in outcomes, cost, as well as comfort. Radial arteryocclusion refers to the blockage of the radial artery. Radial arteryocclusion is a consequence of radial artery cannulation, whichobliterates the radial artery lumen, making it not available for accessin the future.

After instrumentation, it is necessary to compress the radial artery atthe access site to obtain hemostasis of the cannulation wound. Thecannulation wound is an opening of the wall of the radial artery.Hemostasis of the cannulation (or sheath) wound is accomplished byapplying blunt pressure to the radial artery at the cannulation woundsite, or access site. The application of this blunt pressure on theradial artery often causes the artery to occlude or close, therebydenying bloodflow further downstream within the radial artery.Maintaining blood flow in the radial artery while compressing the accesssite, after instrumentation, reduces the risk of post-instrumentationradial artery occlusion. Patent hemostasis is therefore understood tomean achieving the cessation of bleeding at the cannulation wound(access site) of the radial artery, while blood is allowed to flowthrough the artery.

The following references are representative of the field pertaining tothe present invention:

For example, U.S. Pat. No. 6,355,026 to Mick describes right and leftcoronary catheters that are designed to be used in a transradialcoronary catheterization. Also discussed are methods of inserting thecatheters into a right or left coronary artery by a transradialapproach.

In an article entitled Efficacy and Safety of Transient Ulnar ArteryCompression to Recanalize Acute Radial Artery Occlusion AfterTransradial Catheterization (Am J Cardiol 2011; 107:1698-1701) IvoBernat, MD, and others, discuss a method directed to open an occludedradial artery after the radial artery becomes occluded. In the case ofradial artery occlusion, 3-4 hours after hemostasis of the radialartery, ulnar artery compression was applied to attempt recanalizationof radial artery. Bernat et. al. verified reopening of the radial arteryby administration of heparin and compression of the ulnar artery.

Transradial access is being increasingly used because of its ability toreduce access-site complications and increase patient comfort. Whileperforming transradial catheterization, upon introduction of theintroducer sheath or catheter into the radial artery, it is bestpractice to administer anticoagulant, e.g., unfractionated heparin,bivalirudin or Enoxaparin, to assist in the prevention of radial arteryocclusion, even when the catheterization procedure itself wouldotherwise not require it. Anticoagulants may also be referred to asblood thinners. The prophylactic effect of an anticoagulant such asunfractionated heparin to reduce the occurrence of radial arteryocclusion is dose-dependent with significantly better efficacy withhigher doses. With the administration of 5000 units of unfractionatedheparin or alternatively 50 units per kilogram (kg) of body weight,radial artery occlusion rates have been reported in the range of 4-5%.Doses of heparin to be administered are generally expressed in units ofheparin per kg of body weight. A conventional dose of unfractionatedheparin during a transradial catheterization procedure is about 50 unitsper kg of body weight. A conventional dose of other anticoagulants, suchas Bivalirudin or Enoxaparin is the equivalent of 50 units ofunfractionated heparin per kg of body weight.

In view of the anticoagulant effect of unfractionated heparin, whicheffect typically exceeds the duration of the cardiovascular procedure,the patient is systemically anticoagulated with observed activatedclotting times of approximately 200-225 seconds, while undergoinghemostasis. Optimally, a minimum duration of about 120 minutes ofcompression at the radial artery access site is required to achievehemostasis.

SUMMARY OF INVENTION

A present invention method of catheterization of the radial arterydirected at minimizing occurrences of radial artery occlusion isdisclosed. The method comprises inserting a sheath into the radialartery of a patient at an access site. The desired catheterizationprocedure is then performed using the sheath to access the radialartery. Once the catheterization procedure is complete, an ulnarpressure is applied to the homolateral ulnar artery at an ulnar pressuresite while the sheath remains inserted in the radial artery. The sheathis then removed from the radial artery while maintaining the ulnarpressure to the ulnar artery. Once the sheath is removed, and whilecontinuing to apply the ulnar pressure, pressure is applied to theradial artery at the access site to obtain hemostasis at the accesssite.

In a preferred embodiment, the step of “applying a pressure to theradial artery at the access site to obtain hemostasis at the accesssite” is accomplished while maintaining the ulnar pressure to the ulnarartery.

In an embodiment of the present invention, a further step includesconfirming that the step of applying ulnar pressure has reduced bloodflow through the ulnar artery by monitoring flow of the ulnar arteryprior to and after applying the ulnar pressure. In a further embodiment,monitoring flow of the ulnar artery includes sensing skin blood flowand/or pulsation at a fingertip or other location downstream of theulnar pressure site. Digital plethysmography is employed in a preferredembodiment.

In another embodiment, the method further includes confirming patency ofthe radial artery during the step of applying a pressure to the radialartery by sensing skin blood flow and/or pulsation at a fingertip orother location downstream of the access site. In this embodiment, thesensing is performed while the ulnar artery is fully compressed(allowing no flow through the ulnar artery) and/or partially compressed(allowing less flow than when not compressed at all). Patency isconfirmed, in an embodiment, by obtaining a metric relating to thesensing and comparing the metric with a standard metric for the patient,or with a previously-sensed metric. Preferably, the previously sensedmetric is read after the applying the ulnar pressure step and before thestep of removing the sheath from the radial artery. Digitalplethysmography is employed in a preferred embodiment. In yet anotherembodiment, the method further includes administering anticoagulant at adose lower than a conventional dose when an increased flow of blood isprovided in the artery that is punctured at the access site.

In an embodiment of the present invention method, the step ofcompressing the ulnar artery includes: providing an ulnar impinger,securing the ulnar impinger over the wrist such that the impingercontacts a first location over the ulnar artery, and activating theimpinger to press on the ulnar artery at the first location.

In a preferred embodiment of the present invention, the step ofcompressing the ulnar artery includes: providing an ulnar impingementband having an inflatable bladder, securing the ulnar impingement bandover the wrist such that the bladder contacts a first location over theulnar artery, and inflating the bladder to impinge upon the ulnar arteryat the first location.

There is further disclosed a device for use in applying a compressingforce to the ulnar artery of a patient. The device includes a trunkhaving an inflatable bladder. The trunk is defined by a lower portionand an upper portion. The bladder is defined by an expandableenvelopment existing between the lower portion and the upper portion. Apair of limbs are connected to and extend from the upper portion of thetrunk. Together, the pair of limbs and the trunk form a general Y-shape.A first limb of the pair of limbs is adapted to lay across the palm of ahand, between the thumb and the index finger and connect to the trunk tosecure the first limb to the trunk and to secure the bladder to aportion of the patient's wrist corresponding with a first location overthe ulnar artery. A second limb of the pair of limbs is adapted to layover the wrist/distal forearm and connect to the trunk. This is tosecure the second limb to the trunk and to further secure the bladder tothe first location over the ulnar artery. One or more connectors areutilized for fixing the pair of limbs to the trunk.

In use, the bladder is located at the first location over the ulnarartery, and the pair of limbs are fixed around the hand and wrist to thetrunk with the connectors. The bladder is inflated with a tube connectedto an inflator to cause the bladder to impinge upon the ulnar artery atthe first location.

There is further disclosed a device for use in applying a compressingforce to the ulnar artery of a patient. The device comprises a trunkhaving an impinger. The trunk is defined by a lower portion and an upperportion. The impinger is defined by any device sufficient to apply acompression force. A pair of limbs are connected to and extend from theupper portion of the trunk. The pair of limbs together with the trunkform a general Y-shape. A first limb of the pair of limbs is adapted tolay across the palm of a hand, between the thumb and the index finger.The first limb connects to the trunk to secure the first limb to thetrunk, and also to secure the impinger to a portion of the patient'swrist corresponding with a first location over the ulnar artery. Asecond limb of the pair of limbs is adapted to lay over the wrist/distalforearm and connect to the trunk to secure the second limb to the trunkand to further secure the bladder to the first location over the ulnarartery. One or more connectors are employed to fix the pair of limbs tothe trunk. In use, the impinger is located at the first location overthe ulnar artery. The pair of limbs are fixed around the hand and wristto the trunk with the connectors. The impinger is activated to cause thebladder to impinge upon the ulnar artery at the first location.

Additional features, advantages, and embodiments of the invention may beset forth or are apparent from consideration of the following detaileddescription, drawings, and claims. Moreover, it is to be understood thatboth the foregoing summary of the invention and the following detaileddescription are exemplary and intended to provide further explanationwithout limiting the scope of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate preferred embodiments of theinvention and together with the detailed description serve to explainthe principles of the invention. In the drawings:

FIG. 1 is schematic layout of methods disclosed herein;

FIG. 2 is a plan view of the ulnar impingement device according to anembodiment of the present invention;

FIG. 3 is a view showing the ulnar impingement device applied to apatient according to an embodiment of the present invention;

FIG. 4 is another view showing the bladder or impinger of the ulnarimpingement device applied to a patient according to an embodiment ofthe present invention;

FIG. 5 is a view showing the ulnar impingement device applied to apatient showing the top of the hand according to an embodiment of thepresent invention;

FIG. 6 is an isometric view of the ulnar impingement device shown withtrunk fastened to the pair of limbs.

FIG. 7 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is compressed to a point of occlusionintermittently over the duration of time to obtain hemostasis of theradial artery.

FIG. 8 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is compressed partially over the duration oftime to obtain hemostasis of the radial artery.

FIG. 9 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is compressed partially and intermittently overthe duration of time to obtain hemostasis of the radial artery.

FIG. 10 is a schematic depiction of an embodiment of the inventionwherein partial compression of the ulnar artery is maintained for a partof the duration of time required to obtain hemostasis of the radialartery.

FIG. 11 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is fully compressed for a fraction of theduration of time required to obtain hemostasis of the radial artery andpartially compressed for the remainder of the period.

FIG. 12 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is fully compressed for a fraction of theduration of time required to obtain hemostasis of the radial artery andpartially compressed for the remainder of the period.

FIG. 13 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is fully compressed for a fraction of the timerequired to obtain hemostasis of the radial artery, the compressiveforce is then released in a stepwise manner. The compression and therelease is then repeated.

FIG. 14 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is fully compressed for a fraction of the timerequired to obtain hemostasis of the radial artery, the compressiveforce is then released in a stepwise manner.

FIG. 15 is a schematic depiction of an embodiment of the inventionwherein the ulnar artery is fully compressed for a part of duration oftime required to obtain hemostasis of the radial artery.

FIG. 16 is a schematic diagram of an embodiment of the inventiondepicting the steps to obtain patent hemostasis of the radial artery bycompressing the ulnar artery.

FIG. 17 is a schematic diagram of an embodiment of the inventiondepicting the steps to obtain patent hemostasis of the radial artery bycompressing the ulnar artery.

FIG. 18 is a graph showing comparative findings of radial arterypatency.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The invention is directed to a method of obtaining patent hemostasis ofthe radial artery by compressing the un-instrumented ulnar artery toincrease radial artery flow while applying pressure to the radial arteryaccess site. The invention further concerns a device for applying bluntpressure to the ulnar artery, and a method of use.

A present invention method of catheterization of the radial arterydirected at minimizing occurrences of radial artery occlusion isdisclosed. Referring to FIG. 1 specifically, and the Figures in general,the method 1000 comprises inserting a sheath into the radial artery of apatient at an access site. A sheath, as disclosed herein, is understoodto encompass any device inserted into the radial artery and used topermit the access of instrumentation into the radial artery. The desiredcatheterization procedure is then performed using the sheath to provideinstrumentation access the radial artery.

Once the catheterization procedure is complete, an ulnar pressure isapplied to the homolateral ulnar artery at an ulnar pressure site whilethe sheath remains inserted in the radial artery. The sheath is thenremoved from the radial artery while maintaining the first pressure tothe ulnar artery. Once the sheath is removed, and while continuing toapply the ulnar pressure, pressure is applied to the radial artery atthe access site to obtain hemostasis at the access site.

In a preferred embodiment, the step of “applying a pressure to theradial artery at the access site to obtain hemostasis at the accesssite” is accomplished while maintaining the first pressure to the ulnarartery.

The radial artery and the ulnar artery are the two conduits for the flowof oxygenated blood to the hand. The arteries are interconnected andtherefore form an interdependent flow network. When flow is reduced inone of the arteries, by compression for example, flow increases in theother artery. When the ulnar artery is compressed, flow in the ulnarartery is reduced, which causes an increase in pressure and flow in theradial artery. When the radial artery is compressed, flow in the radialartery is reduced, which causes an increase in pressure and flow in theulnar artery.

In an embodiment, a further step includes confirming that theapplication of ulnar pressure has reduced blood flow through the ulnarartery. This is done by monitoring flow of the ulnar artery prior to andafter applying the ulnar pressure. In a further embodiment, monitoringflow of the ulnar artery includes sensing skin blood flow and/orpulsation at a fingertip or other location downstream of the ulnarpressure site. Digital plethysmography is employed in one embodiment.

In another embodiment, the method 1000 further includes confirmingpatency of the radial artery during the step of applying a pressure tothe radial artery. In a preferred embodiment, patency is accomplished bysensing skin blood flow and/or pulsation at a fingertip or otherlocation downstream of the access site. Other sensing locations bothupstream and downstream may be used to confirm patency of the radialartery. In the preferred embodiment, the sensing is performed while theulnar artery is fully compressed (allowing no flow through the ulnarartery) and/or partially compressed (allowing less flow than when notcompressed at all). Patency is confirmed, in an embodiment, by obtaininga metric relating to the sensing and comparing the metric with astandard metric for the patient, or with a previously-sensed metric.Metric is understood to mean a sensible, quantifiable value or reading,relating to the characteristic sensed. Preferably, the previously sensedmetric is read after the applying the ulnar pressure step and before thestep of removing the sheath from the radial artery. Digitalplethysmography is employed, in a preferred embodiment, to obtain themetrics. Other sensing modes may be employed, so long as the selectedmode is capable of confirming patency in one form or another.

In an embodiment of the present invention method 1000, the step ofcompressing the ulnar artery includes: providing an ulnar impinger,securing the ulnar impinger over the wrist such that the impingercontacts a first location over the ulnar artery, and activating theimpinger to press on the ulnar artery at the first location. In apreferred embodiment, the first location is over the Guyon's canal,demarcated by pisiform bone on the medial aspect, directly over theulnar artery pulse.

Impinger is understood to include any device capable of applying a forceto the ulnar artery, whether alone or part of a system, sufficient tocompress the ulnar artery. One exemplary class includes mechanicaldevices that expand in size to cause a band surrounding the wrist toconstrict an object to compress the ulnar artery. Another exemplaryclass of impingers includes mechanical devices that constrict a bandworn around the wrist sufficient to cause an object to press on theulnar artery.

In a preferred embodiment, the step of compressing the ulnar arteryincludes: providing an ulnar impingement band having an inflatablebladder, securing the ulnar impingement band over the wrist such thatthe bladder contacts a first location over the ulnar artery, andinflating the bladder to impinge upon the ulnar artery at the firstlocation.

Turning to the Figures generally, and particularly FIGS. 2-6, there isfurther disclosed a device 11 for use in applying a compressing force tothe ulnar artery of a patient. The device 11 includes a trunk 13 havingan inflatable bladder 15. The trunk 13 is defined by a lower portion 13a and an upper portion 13 b. The bladder 15 is defined by an envelopment17 existing between the lower portion 13 a and the upper portion 13 b. Apair of limbs 19 are connected to and extend from the upper portion 13 bof the trunk 13. Together, the pair of limbs 19 and the trunk 13 form ageneral Y-shape. Preferably, the pair of limbs 19 and the trunk 13 areplanar and form a Y-shape band. A first limb 19 a of the pair of limbs19 is adapted to lay across the palm of a hand, between the thumb andthe index finger. The first limb 19 a is adapted to connect to the trunk13 for securing the first limb 19 a to the trunk 13 and for securing thebladder 15 to a portion of the patient's wrist corresponding with afirst location 25 over the ulnar artery. A second limb 19 b of the pairof limbs 19 is adapted to lay over the wrist/distal forearm and connectto the trunk 13. This is to secure the second limb 19 b to the trunk 13and to further secure the bladder 15 to the first location 25 over theulnar artery. One or more connectors 21 are utilized for fixing the pairof limbs 19 to the trunk 13. In a preferred embodiment, the connector isVelcro.

In use, the bladder 15 is located at the first location 25 over theulnar artery, and the pair of limbs 19 are fixed around the hand andwrist to the trunk 13 with the connectors 21. The bladder 15 is inflatedwith a tube connected to an inflator to cause the bladder 15 to impingeupon the ulnar artery at the first location 25.

There is further disclosed a device 13 for use in applying a compressingforce to the ulnar artery of a patient. The device 13 comprises a trunk13 having an impinger 23. The trunk 13 is defined by a lower portion 13a and an upper portion 13 b. The impinger 23 is defined by any devicesufficient to apply a compression force. Examples include expandingsprings, expanding screw-type appurtenances, or other devices andsystems as discussed herein. A pair of limbs 19 are connected to andextend from the upper portion 13 b of the trunk 13. The pair of limbs 19together with the trunk 13 form a general Y-shape. A first limb 19 a ofthe pair of limbs 19 is adapted to lay across the palm of a hand,between the thumb and the index finger. The first limb 19 a connects tothe trunk 13 to secure the first limb 19 a to the trunk 13, and also tosecure the impinger 23 to a portion of the patient's wrist correspondingwith a first location 25 over the ulnar artery. A second limb 19 b ofthe pair of limbs 19 is adapted to lay over the wrist/distal forearm andconnect to the trunk 13 to secure the second limb 19 b to the trunk 13and to further secure the impinge 23 to the first location over theulnar artery. One or more connectors 21 are employed to fix the pair oflimbs 19 to the trunk 13. In use, the impinger 23 is located at thefirst location 25 over the ulnar artery. The pair of limbs 19 are fixedaround the hand and wrist to the trunk 13 with the connectors 21. Theimpinger 23 is activated to cause the impinger 23 to impinge upon theulnar artery at the first location 25.

In another embodiment of the present invention method 1000, anintroducer sheath and/or a catheter is placed in a radial artery aftersterile preparation as well as with administration of local anesthetic.The radial artery is punctured at an access site and, after placement ofa guidewire, either an introducer sheath or a catheter is introduced inthe radial artery lumen. The catheterization procedure is performed in amanner deemed appropriate by the operator.

In one embodiment, the present invention method further comprisesadministering an anticoagulant at any time after introduction of thecatheter or introducer sheath and before removal of the catheter or theintroducer sheath. In another embodiment, an anticoagulant isadministered before the introduction of the catheter or introducersheath. Examples of anticoagulants include, without limitation,unfractionated heparin, bivalirudin or Enoxaparin. In one embodiment,wherein a method for obtaining patent hemostasis at an access site of anartery comprises increasing the flow of blood in the artery that ispunctured at the access site, unfractionated heparin is administered ata dose that is lower than a conventional dose.

The flow of blood is increased in the radial artery if the radial arteryis punctured for catheterization; the flow of blood is increased in theulnar artery if the ulnar artery is punctured for catheterization; theflow of blood is increased in femoral artery if the femoral artery ispunctured for catheterization; or the flow of blood is increased in anyother artery that is punctured at an access site. The flow of blood inan artery can be increased by different techniques. For example, theflow of blood in artery can be increased by a pharmacological method,e.g., administration of a drug. Examples of drugs that can be used toincrease the flow of blood in an artery include vasodilators that reducedistal resistance and increase proximal flow, which include allvasodilator agents (e.g., nitrates, calcium channel blockers) or agentsthat increase cardiac output (e.g., dobutamine, epinephrine, milrinone).The flow of blood in an artery can also be increased using externalforces. For example, flow of blood in a radial artery can be increasedby applying a compressive force on the ulnar artery, and the flow ofblood in the ulnar artery can be increased by applying a compressiveforce on the radial artery. The flow of blood in an artery could also beincreased by using mechanical devices, e.g., pump. The device could beimplantable in the human body or external to the human body. Forexample, use of a pump to increase flow of blood in a femoral artery isknown in the art.

Increasing the flow of blood in an artery leads to an increase in thevelocity of blood in the artery. The increase in velocity results indecrease in residence time or contact time of blood at the puncture siteon the artery. The residence time or contact time (t, seconds) iscalculated by dividing the diameter (d, mm) of the puncture hole withthe velocity (v, mm/second) of the blood in the artery. t=d/v. For agiven puncture hole with diameter (d), higher the velocity (v), lower isthe contact time t. A lower contact time results in lower exposure ofblood to external environment thereby lowering the potential fortransmural clotting and vessel lumen occlusion during thecatheterization procedure. A lower than conventional dose ofanticoagulant can then be used by increasing the flow of blood in anartery punctured for a catherization procedure.

In one embodiment, a method of reducing dosage of an anticoagulant whenperforming a catheterization procedure at an access site of an arterycomprises administering the anticoagulant at a dosage less than aconventional dose of an equivalent of 50 units of unfractionated heparinper kg of body weight, obtaining an increase in velocity of blood in theartery that is punctured at the access site, and maintaining theincrease in the velocity of blood in the artery for a period of timeduring the catheterization procedure. In another embodiment, a method ofreducing a dosage of an anticoagulant when performing a catheterizationprocedure at an access site of an artery comprises administering theanticoagulant at a dose less than a conventional dose of an equivalentof 50 units of unfractionated heparin per kg of body weight, reducing acontact time of blood at the access site of the artery, and maintainingthe contact time of blood at a reduced level for a period of time duringthe catheterization procedure. Unfractionated heparin or anotheranticoagulant may be used at a dose that is lower than a conventionaldose. An anticoagulant is selected from a group comprising heparin,dalteparin, Fragmin®, danaparoid, enoxaparin, unfractionated heparin,other low molecular weight heparin, direct thrombin inhibitors includinghirudin, argatroban, bivalirudin and all substances derived from and/orrelated to the foregoing substances.

In one embodiment, the anticoagulant is unfractionated heparin and thedosage of the unfractionated heparin is less than 50 units per kilogramof body weight, administered parenterally. In yet another embodiment,the dosage of unfractionated heparin is about 25 units per kilogram ofbody weight. In another embodiment, the dosage of unfractionated heparinis less than 25 units per kilogram of body weight. In yet anotherembodiment, the dosage of unfractionated heparin is in the range of20-40 units per kilogram of body weight. In another embodiment, thedosage of unfractionated heparin is in the range of 15-30 units perkilogram of body weight. The dosage of other anticoagulants is similarto dosage of unfractionated heparin and is measured as equivalent ofunits of unfractionated heparin per kg of body weight.

After completion of the catheterization procedure, the present inventionmethod comprises applying hemostatic compression to the access siteusing a device. In one embodiment, the device is a band having at leasttwo inflatable bladders wherein one inflatable bladder is used to applycompressive hemostatic pressure at the access site on the radial artery,and a second inflatable bladder is used to apply an ulnar pressure at anulnar pressure site. In another embodiment, a device such as an impingerthat is capable of applying a mechanical compressive force is used toapply the ulnar pressure. In yet another embodiment, a device such as animpinger that is capable of applying a mechanical compressive force isused to apply the compressive hemostatic pressure at the access site onthe radial artery. In another embodiment, a band with at least oneinflatable bladder is used to apply compressive hemostatic pressure atthe access site on the radial artery, and another device is used toapply ulnar pressure at an ulnar pressure site. Manual compression mayalso be used.

The band having at least two inflatable bladders is wrapped around thewrist of a patient, and secured near both ends of the band withfastener. In one embodiment, the first bladder covering the puncturesite on the radial artery is filled with air to apply a first occlusivepressure to the radial artery, thereby stopping both bleeding andintra-arterial blood flow at the puncture site. Then, the second ballooncovering the ulnar artery is filled with air to apply a second occlusivepressure to the ulnar artery, thereby stopping intra-arterial bloodflow. As a result, there will be limited blood supply to the hand asocclusive pressure on both the radial artery and the ulnar artery hasbeen applied. Subsequently, pressure on the radial artery is releasedover a period of time by slowly deflating the first bladder until ablood spurt is seen from the puncture site of the radial artery underthe first bladder. Once blood flow from the puncture site has beenobserved, the pressure in the first bladder covering the puncture siteis slightly increased by introducing small amount of air to stop thebleeding. In one embodiment, inflation of the balloons is done manuallyusing syringes to inject fluid, e.g., air in the balloons. In anotherembodiment, deflation of the balloons is also done manually usingsyringes to remove fluid from the balloons. In yet another embodiment,deflation of balloons is done automatically using valves designed toeject fluid from a balloon periodically over a period of time.

In one embodiment of the present invention method, wherein ananticoagulant such as unfractionated heparin is administered to apatient, the method further comprises applying hemostatic compressionfor a time less than 120 minutes. In another embodiment, the hemostaticcompression time is about 60 minutes. In yet another embodiment, thehemostatic compression time is less than 60 minutes. In one embodiment,during the hemostatic compression time when the radial artery iscompressed at the access site, the ipsilateral ulnar artery is alsocompressed simultaneously. In another embodiment, the ipsilateral ulnarartery is compressed continuously during the entire hemostaticcompression time. In yet another embodiment, the ipsilateral ulnarartery is compressed continuously for only a part of the hemostaticcompression time. In another embodiment, the ulnar artery is compressedintermittently during the hemostatic compression time. In someembodiments, the ulnar artery may be compressed fully, and in otherembodiments, the ulnar artery may be compressed partially.

In one embodiment of present invention, a method of obtaining hemostasisof a radial artery of a patient after performing a catheterizationprocedure at an access site of the radial artery, comprises performingthe following steps: (a) applying a hemostatic pressure to the radialartery at the access site; (b) providing an increased flow of blood inthe radial artery; (c) administering a dose of unfractionated heparin tothe patient; and (d) maintaining simultaneously the hemostatic pressureand the increased flow of blood in the radial artery; wherein step (b)comprises applying an ulnar pressure to an ulnar artery at an ulnarpressure site; and wherein step (c) comprises administering the dose ofunfractionated heparin that is less than 50 units per kg body weight.

In another embodiment of present invention, a method of obtaininghemostasis of an artery of a patient after performing a catheterizationprocedure at an access site of the artery, comprises performing thefollowing steps: (i) applying a hemostatic pressure to the artery at theaccess site; (ii) providing an increased flow of blood in the artery;(iii) administering a dose of unfractionated heparin or otheranticoagulant to the patient; and (iv) maintaining simultaneously thehemostatic pressure and the increased flow of blood in the artery for aduration of time; wherein step (iii) comprises administering the dose ofunfractionated heparin that is less than 50 units per kg body weight;and wherein the duration of time in step (iv) is less than 120 minutes.

In yet another embodiment of the present invention, a method ofobtaining hemostasis of a radial artery of a patient after performing acatheterization procedure at an access site of the radial artery,comprising performing the following steps: (A) applying a hemostaticpressure to the radial artery at the access site; (B) providing anincreased flow of blood in the radial artery; (C) administering a doseof an anticoagulant to the patient; and (D) maintaining simultaneouslythe hemostatic pressure and the increased flow of blood in the radialartery for a duration of time; wherein step (B) comprises applying anulnar pressure to an ulnar artery at an ulnar pressure site; wherein thedose of the anticoagulant in step (C) is less than an equivalent of 50units of unfractionated heparin per kg of body weight; and wherein theduration of time in step (D) is less than 120 minutes. In oneembodiment, the increased flow of blood in the radial artery is providedby compressing the ulnar artery.

In one embodiment of the present invention, a hemostatic pressure on theradial artery is applied using a first band comprising at least oneinflatable bladder, wherein the inflatable bladder of the first bandapplies the hemostatic pressure at the access site, and the ulnarpressure is applied using a technique selected from a group consistingof (i) a second band comprising at least one inflatable bladder, whereinthe inflatable bladder of the second band applies a pressure at theulnar pressure site, (ii) a mechanical device applies a compressingforce at the ulnar pressure site; (iii) manual pressure is applied atthe ulnar pressure site.

In one embodiment, after about 60 minutes of compression of the radialartery at the access site, the pressure of compression is graduallyreduced and weaned off from the radial artery access site, and the siteis lightly dressed. In another embodiment, the duration of reducing thecompression and weaning off the hemostatic compression pressure is inthe range of 5-10 minutes. This technique improves patient comfort andincreases the number of patients who can be treated.

In another embodiment, a method of obtaining hemostasis of a radialartery of a patient when performing a catheterization procedure at anaccess site of the radial artery, comprises administering a dose of ananticoagulant to the patient during the catheterization procedure andperforming the following steps: (a) applying a hemostatic pressure tothe radial artery at the access site for a duration of time at leastuntil hemostasis of the radial artery; (b) applying an ulnar pressure toan ulnar artery at an ulnar pressure site to fully compress the ulnarartery, thereby providing an increased flow of blood in the radialartery; (c) applying an ulnar pressure to the ulnar artery at the ulnarpressure site to partially compress the ulnar artery, thereby providingan increased flow of blood in the radial artery; (d) maintainingsimultaneously the hemostatic pressure and the increased flow of bloodin the radial artery; and attaining hemostasis of the radial artery. Inone embodiment, step (b) precedes step (c). In another embodiment, step(c) comprises continuous partial compression of the ulnar artery atleast until hemostasis of the radial artery.

In yet another embodiment, a method of obtaining hemostasis of a radialartery of a patient when performing a catheterization procedure at anaccess site of the radial artery, comprises performing the followingsteps: (a) administering a dose of an anticoagulant to the patientduring the catheterization procedure, (b) applying a hemostatic pressureto the radial artery at the access site for a duration of time at leastuntil hemostasis of the radial artery; (c) applying an ulnar pressure toan ulnar artery at an ulnar pressure site to fully compress the ulnarartery; (d) applying continuously an ulnar pressure to the ulnar arteryat the ulnar pressure site to partially compress the ulnar artery for apart of the duration of time; and attaining hemostasis of the radialartery; wherein step (a) precedes all other steps, and step (c) precedesstep (d).

In another embodiment, a method of obtaining hemostasis of a radialartery of a patient when performing a catheterization procedure at anaccess site of the radial artery, comprises performing the followingsteps: (a) administering a dose of an anticoagulant to the patientduring the catheterization procedure; (b) applying a hemostatic pressureto the radial artery at the access site for a duration of time at leastuntil hemostasis of the radial artery; (c) applying an ulnar pressure toan ulnar artery at an ulnar pressure site to fully compress the ulnarartery; (d) applying an ulnar pressure to the ulnar artery at the ulnarpressure site, wherein the ulnar pressure is applied intermittently; and(e) attaining hemostasis of the radial artery; wherein step (a) precedesall other steps, and step (c) precedes step (d). In yet anotherembodiment, the ulnar pressure in step (d) is applied intermittently atleast until hemostasis of the radial artery.

A period of 2 hours (120 minutes) is the time it typically takes forhemostasis to occur. In practice, the time for hemostasis could last formore than 2 hours or less than 2 hours. An important considerationduring the hemostasis process is hand ischemia. The risk of handischemia has to be minimized and the benefit of patent hemostasismaximized. Because the radial artery is generally compressedcontinuously at the radial puncture site for about 2 hours to obtainhemostasis, one safe approach considering the potential for handischemia is to compress the ulnar artery to a point of occlusionintermittently over the duration of time for hemostasis, i.e.,compressing the ulnar artery fully for several minutes and then removingthe pressure on the ulnar artery for several minutes and repeating thecycle, thereby providing periodic blood flow to the hand during thehemostasis period. FIG. 7 is a schematic depiction of an embodiment ofthe invention wherein the ulnar artery is compressed to a point ofocclusion intermittently over the duration of time to obtain hemostasisof the radial artery. Note that the X-axis in FIG. 7 (and FIGS. 8-15) isthe time taken to obtain hemostasis of the radial artery. FIGS. 7-15show the time as 2 hours, however it should be noted that the time toobtain hemostasis can be more than 2 hours or less than 2 hours. So, forexample, if the time to obtain hemostasis is 1 hour, then the number 2on the X-axis should be replaced with number 1. The Y-axis depicts thecompression of the ulnar artery, i.e., whether the ulnar artery is fullycompressed, partially compressed or not compressed.

In another embodiment of the invention as shown schematically in FIG. 8,patent hemostasis is obtained by compressing the ulnar artery partiallyand maintaining continued partial compression of the ulnar artery whilesimultaneously compressing the radial artery over the duration of timeto obtain hemostasis of the radial artery. Partial compression of theulnar artery would provide some blood flow to the hand. In yet anotherembodiment, the ulnar artery is compressed partially and intermittentlyas shown in FIG. 9. In another embodiment shown schematically in FIG.10, partial compression of the ulnar artery is maintained for a part ofthe duration of time required to obtain hemostasis of the radial artery.In another embodiment, the ulnar artery is compressed partially for afirst period of time, and the pressure is increased to compress theulnar artery fully for a second period of time.

In one embodiment, ulnar artery is compressed continuously for theduration of time at least until hemostasis of the radial artery whereinthe ulnar artery is fully compressed for a fraction of the duration oftime and partially compressed for the remainder of the period. See, forexample, FIGS. 11 and 12. And there are embodiments as shown in FIGS. 13and 14 wherein the ulnar artery is fully compressed for a fraction ofthe time required to obtain hemostasis of the radial artery, thecompressive force is then released in a stepwise manner. In yet anotherembodiment, the compressive force is released in a linear manner or acontinuous curvilinear manner rather than a stepwise manner over aperiod of time. In another embodiment of the method invention depictedin FIG. 15, the ulnar artery is fully compressed for a part of durationof time required to obtain hemostasis of the radial artery.

In an embodiment of the invention, a band comprising a radial balloonand an ulnar balloon is applied to the instrumented forearm with theradial balloon above or at the radial puncture site, and the distal endof the band aligned with the crease of the wrist at the distal end ofthe forearm. The ulnar balloon is inflated to totally occlude the ulnarartery flow at the outset. Then inflate the radial balloon, and removethe introducer sheath, observe the puncture site and inflate the radialballoon to the point where there is no further bleeding from the radialpuncture site. In about 15 minutes after full compression of the ulnarartery, and no later than 30 minutes, deflate the ulnar balloon to allowflow in the ulnar artery, making the ulnar artery partially compressed.In another embodiment, reduce the pressure on the ulnar artery to zeroin the time range of about 15 minutes to about 30 minutes after fullcompression of the ulnar artery. Adjust the pressure in the radialballoon to allow for radial artery patency and for maintenance of radialhemostasis. Deflate the ulnar balloon partially or fully at any point ifthe patient experiences discomfort at the ulnar compression site.

In another embodiment as shown in FIG. 16, after completing thecatheterization procedure, pressure is applied to ulnar artery to fullycompress the ulnar artery and pressure is applied to the puncture siteof the radial artery to stop bleeding. In one embodiment, pressure isapplied to the ulnar artery before the pressure is applied to the radialartery. In another embodiment, pressure is applied to the radial arterybefore the pressure is applied to the ulnar artery. Measure time fromthe time ulnar artery was fully compressed. At time=T1 from the timeulnar artery was fully compressed, check whether the radial artery ispatent. If the radial artery is patent, deflate the ulnar balloon topartially compress the ulnar artery. If the radial artery is not patentat time=T1, continue full compression of the ulnar artery until time=T2.Check again the patency of radial artery at time=T2. If the radialartery is not found to be patent at time=T2, reduce the pressure at thepuncture site of the radial artery provided there is no bleeding. Also,at time=T2, reduce the pressure on the ulnar artery to make the ulnarartery partially compressed irrespective of whether the radial artery ispatent or not patent. In one embodiment, T1 is about 15 minutes and T2is about 30 minutes. Continue compression of radial artery untilhemostasis at the puncture site. In one embodiment, continue partialcompression of ulnar artery at least until hemostasis of the radialartery. In another embodiment, reduce the pressure on the ulnar arteryto zero before hemostasis of the radial artery. In another embodiment,reduce the pressure on the ulnar artery to zero at T2=15 minutes. In yetanother embodiment, reduce the pressure on the ulnar artery to zero atT2=30 minutes. In one embodiment T1 is half of T2.

In another embodiment as shown in FIG. 17, after completing thecatheterization procedure, pressure is applied to ulnar artery to fullycompress the ulnar artery and pressure is applied to the puncture siteof the radial artery to stop bleeding. In one embodiment, pressure isapplied to the ulnar artery before the pressure is applied to the radialartery. In another embodiment, pressure is applied to the radial arterybefore the pressure is applied to the ulnar artery. At time=T1 from thetime ulnar artery was fully compressed, check whether the radial arteryis patent. If the radial artery is not found to be patent at time=T1,reduce the pressure at the puncture site of the radial artery providedthere is no bleeding. Continue full compression of ulnar artery. Checkagain the patency of radial artery at time=T2. If the radial artery isnot found to be patent at time=T2, further reduce the pressure at thepuncture site of the radial artery provided there is no bleeding. Also,at time=T2, reduce the pressure on the ulnar artery to make the ulnarartery partially compressed irrespective of whether the radial artery ispatent or not patent. In one embodiment, T1 is about 15 minutes and T2is about 30 minutes. Continue compression of radial artery untilhemostasis at the puncture site. In one embodiment, continue partialcompression of ulnar artery at least until hemostasis of the radialartery. In another embodiment, reduce the pressure on the ulnar arteryto zero before hemostasis of the radial artery. In another embodiment,reduce the pressure on the ulnar artery to zero at T2=15 minutes. In yetanother embodiment, reduce the pressure on the ulnar artery to zero atT2=30 minutes. In one embodiment T1 is half of T2.

FIG. 18 shows comparative findings of radial artery patency using aprotocol compressing ipsilateral ulnar artery completely to the point ofverified occlusion for a duration of 2 hours (PROPHET-II protocol)versus compression of ipsilateral ulnar artery completely for the first30 minutes of simultaneous instrumented radial artery compression, afterwhich the ipsilateral ulnar artery compression was released. The x-axisof the graph in FIG. 18 is the time from onset of compression of theinstrumented radial artery and ipsilateral ulnar artery. The y-axis ofthe graph in FIG. 18 is the percentage of patients with patency in theradial artery. The patency was tested every 30 minutes. The radialpatency with either of these strategies was comparable at the completionof radial artery hemostatic compression at 2 hours.

It will be appreciated that several of the above-disclosed and otherfeatures and functions, or alternatives or varieties thereof, may bedesirably combined into many other different methods, systems orapplications. Also, that various alternatives, modifications, variationsor improvements therein may be subsequently made by those skilled in theart which are also intended to be encompassed by the following claims.

In the description above, for the purposes of explanation, numerousspecific requirements and several specific details have been set forthin order to provide an understanding of certain embodiments. It will beapparent however, to one skilled in the art, that one or more otherembodiments may be practiced without one or more of these specificdetails. The particular embodiments described are not provided to limitthe invention, but to illustrate it. The scope of the invention is notto be determined by the specific examples provided above. In otherinstances, well-known structures, devices, and operations have beenshown in block diagram form or without detail in order to avoidobscuring the understanding of the description. Where consideredappropriate, reference numerals or terminal portions of referencenumerals have been repeated among the figures to indicate correspondingor analogous elements, which may optionally have similarcharacteristics.

It should also be appreciated that reference throughout thisspecification to “one embodiment”, “an embodiment”, “one or moreembodiments”, or “different embodiments”, for example, means that aparticular feature may be included in the practice of the invention.Similarly, it should be appreciated that in the description variousfeatures are sometimes grouped together in a single embodiment, figure,or description thereof to streamlining the disclosure and aiding in theunderstanding of various inventive aspects. This method of disclosure,however, is not to be interpreted or construed as reflecting anintention that the invention requires more features than are expresslyrecited in each claim. Rather, as the following claims reflect,inventive aspects may lie in less than all features of a singledisclosed embodiment. In another situation, an inventive aspect mayinclude a combination of embodiments described herein or in acombination of less than all aspects described in a combination ofembodiments.

The invention claimed is:
 1. A method of attaining hemostasis of aradial artery of a patient after performing a catheterization procedureat an access site on the radial artery, comprising performing thefollowing steps: (a) applying a radial pressure on the radial artery byinflating at least a first bladder to stop bleeding at the access site;(b) applying an ulnar pressure on an ulnar artery by inflating at leasta second bladder at an ulnar pressure site; (c) continuing to apply theradial pressure on the radial artery for a duration of time to attainhemostasis of the radial artery; (d) continuing to apply the ulnarpressure on the ulnar artery at the ulnar pressure site to compress theulnar artery fully for a first period of time, wherein the first periodof time is at least 15 minutes; and (e) attaining hemostasis of theradial artery; wherein the first period of time is less than theduration of time to attain hemostasis of the radial artery, whereby theulnar pressure is reduced to zero for a second period of time up untiland including the moment in which hemostasis of the radial artery isattained.
 2. The method of claim 1, wherein step (b) precedes step (a).3. The method of claim 1, wherein an introducer sheath used in thecatheterization procedure is removed after step (b).
 4. The method ofclaim 1, further comprising a step of confirming patency of the radialartery.
 5. The method of claim 1, wherein the ulnar pressure site is aGuyon's canal.
 6. The method of claim 1, further comprisingadministering a dose of an anticoagulant at any time before introductionof a catheter or an introducer sheath, or administering theanticoagulant at any time after introduction of a catheter or anintroducer sheath and before removal of the catheter or the introducersheath.
 7. The method of claim 6, wherein the anticoagulant is selectedfrom a group consisting of: heparin, dalteparin, danaparoid, enoxaparin,unfractionated heparin, low molecular weight heparin, direct thrombininhibitors including hirudin, argatroban, bivalirudin, and combinationsor derivatives thereof.
 8. The method of claim 6, wherein the dose ofthe anticoagulant is less than an equivalent of about 50 units ofunfractionated heparin per kg of body weight.
 9. The method of claim 1,wherein the duration of time in step (c) is less than 120 minutes. 10.The method of claim 1, wherein the duration of time in step (c) is about60 minutes.
 11. The method of claim 1, wherein the first bladder and thesecond bladder are connected to a band.
 12. The method of claim 1,further comprising a step of slowly reducing compression of the radialartery until bleeding just starts, and then increasing compressionslightly to stop bleeding.
 13. The method of claim 12, wherein the stepof slowly reducing compression of the radial artery until bleeding juststarts, and then increasing compression slightly to stop bleeding isperformed after step (d).
 14. A method of attaining hemostasis of aradial artery of a patient after performing a catheterization procedureat an access site on the radial artery, comprising performing thefollowing steps: (a) applying a radial pressure on the radial artery byinflating at least a first bladder to stop bleeding at the access site;(b) applying an ulnar pressure on an ulnar artery by inflating at leasta second bladder at an ulnar pressure site; (c) continuing to apply theradial pressure on the radial artery for a duration of time to attainhemostasis of the radial artery; (d) continuing to apply the ulnarpressure on the ulnar artery at the ulnar pressure site to compress theulnar artery fully for a first period of time, wherein the first periodof time is either about 15 minutes or about 30 minutes; and (e)attaining hemostasis of the radial artery; wherein the first period oftime is less than the duration of time to attain hemostasis of theradial artery, whereby after the first period of time the ulnar pressureis reduced to zero for a second period of time up until and includingthe moment in which hemostasis of the radial artery is attained.
 15. Themethod of claim 14, wherein the first bladder and the second bladder areconnected to a band.
 16. The method of claim 14, further comprisingadministering a dose of an anticoagulant at any time before introductionof a catheter or an introducer sheath, or administering theanticoagulant at any time after introduction of a catheter or anintroducer sheath and before removal of the catheter or the introducersheath, and the dose of the anticoagulant is less than an equivalent ofabout 50 units of unfractionated heparin per kg of body weight.
 17. Themethod of claim 14, further comprising a step of slowly reducingcompression of the radial artery until bleeding just starts, and thenincreasing compression slightly to stop bleeding.
 18. The method ofclaim 14, wherein the duration of time in step (c) is less than 120minutes.